txpool: add txpool_contentFrom, fix txpool_status hex format, fix txpool_content

[svlachakis]

Fixes Closes Resolves #11308

Changes

• txpool_content — requires checksumed addresses

• txpool_status — pending and queued were serialized as raw integers (e.g. 1010). The spec defines them as uint (hex-encoded quantity). Updated the property type from int to long so LongConverter produces the correct wire format (e.g. "0x3f2").

• txpool_contentFrom — method was missing entirely. Added:

  • ITxPoolRpcModule.txpool_contentFrom(Address address)
  • TxPoolContentFrom response model — filters pool content to a single sender, returning:

    {
      "pending": { "nonce → tx" },
      "queued": { "nonce → tx" }
    }

    (without the address level)
  • Implementation in TxPoolRpcModule

• txpool_content — no changes needed; nonce keys already serialize as decimal strings (spec requirement) via STJ’s default ulong dictionary key behavior, and blockHash / blockNumber / blockTimestamp / transactionIndex are already null with from present.

---

Tests

Added serialization-level tests via RpcTest.TestSerializedRequest to validate the actual JSON wire format:

• txpool_status emits "0xa" instead of 10
• Nonce map keys are decimal strings ("806") instead of hex ("0x326")
• Pending transactions always include null block fields and from
• txpool_contentFrom filters correctly and serializes empty maps as {}

Types of changes

What types of changes does your code introduce?

• Bugfix (a non-breaking change that fixes an issue)
• New feature (a non-breaking change that adds functionality)
• Breaking change (a change that causes existing functionality not to work as expected)
• Optimization
• Refactoring
• Documentation update
• Build-related changes
• Other: Description

Testing

Hive tests: https://github.com/NethermindEth/nethermind/actions/runs/24787512946

Requires testing

• Yes
• No

If yes, did you write tests?

• Yes
• No

[claude]

Claude finished @svlachakis's task in 5m 17s —— View job

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PR Review: txpool: add txpool_contentFrom, fix txpool_status hex format

• Gather context and read relevant files
• Review changed files for correctness, security, and performance
• Check adherence to repo rules
• Post findings

---

Summary

The bug fix for txpool_status is correct: changing Pending/Queued from int (using IntConverter → decimal) to long (using LongConverter → hex) matches the execution-apis spec. The txpool_contentFrom implementation is also correct — Dictionary<ulong, TransactionForRpc> keys serialize as decimal strings by default (no WriteAsPropertyName override on ULongConverter), which is what the spec requires. Test coverage is solid and follows existing patterns.

---

Findings

Medium

#	File	Issue
1	TxPoolContentFrom.cs	File naming inconsistency — All sibling files use TransactionPool*.cs: TransactionPoolContent.cs, TransactionPoolStatus.cs, TransactionPoolInspection.cs. The new file should be TransactionPoolContentFrom.cs. (Inline comment posted)

Low

#	File	Issue
2	TransactionPoolStatus.cs:11-12	Sum() returns int before widening — Enumerable.Sum(Func<T, int>) accumulates in int and overflows at ~2.1B entries before the implicit widening to long. Won't happen in practice, but cast inside the lambda: Sum(static t => (long)t.Value.Count). (Inline comment posted)
3	TransactionPoolStatus.cs	long vs ulong — Pool counts are semantically non-negative; ulong would be more precise. Both serialize identically as hex via their converters, so this is cosmetic.
4	TxPoolContentFrom.cs	Missing XML doc comments — Coding rules require XML docs for all public APIs. The class and its Pending/Queued properties have none.

---

What's correct

• IntConverter.Write → WriteNumberValue (decimal) was the actual bug; LongConverter.Write → NumericConverterHelper.Write (hex) is the correct fix. ✓
• ulong dictionary keys fall back to STJ's built-in decimal property-name behavior (no WriteAsPropertyName on ULongConverter), producing "806" not "0x326". ✓
• TxPoolContentFrom.MapTransactions uses manual iteration — correct per the no-LINQ-on-simple-loops rule. ✓
• Empty address returns new Dictionary<ulong, TransactionForRpc>(0) → serializes as {}. ✓
• File-scoped namespaces on new/modified files. ✓
• Test coverage validates wire format, empty cases, and filtering. ✓

[claude]

Medium — File naming inconsistency

The sibling files in this directory follow a TransactionPool*.cs naming convention:

• TransactionPoolContent.cs → class TxPoolContent
• TransactionPoolStatus.cs → class TxPoolStatus
• TransactionPoolInspection.cs → class TxPoolInspection

This new file breaks that pattern. It should be renamed to TransactionPoolContentFrom.cs for consistency.

Fix this →

[svlachakis]

@claude review again please

[claude]

Claude finished @svlachakis's task in 4m 7s —— View job

---

PR Review: txpool: add txpool_contentFrom, fix txpool_status hex format

• Gather context and read relevant files
• Review changed files for correctness, security, and performance
• Check adherence to repo rules
• Post findings

---

Summary

All three findings from the previous review have been addressed. The implementation is correct and the PR is in good shape.

---

Previous findings — status

#	Severity	Finding	Status
1	Medium	File naming: TxPoolContentFrom.cs should be TransactionPoolContentFrom.cs	✅ Resolved — file is TransactionPoolContentFrom.cs
2	Low	Sum() accumulates in int, overflows before widening to long	✅ Resolved — (ulong)info.Pending.Sum(static t => (long)t.Value.Count)
3	Low	long vs ulong for pool counts	✅ Resolved — now ulong
4	Low	Missing XML doc comments on TxPoolContentFrom	✅ Resolved — class summary and property <summary> docs added

---

New findings

Low

#	File	Issue
1	ITxPoolRpcModule.cs:22	ExampleResponse is missing blockTimestamp — TransactionForRpc.BlockTimestamp is declared [JsonIgnore(Condition = JsonIgnoreCondition.Never)], so it serializes as "blockTimestamp":null for mempool transactions. The example string omits this field. Not runtime-impacting, but the doc example is inaccurate.

---

What's correct

• ulong Pending/Queued → ULongConverter → NumericConverterHelper.Write → hex string in JSON-RPC Hex mode. Both ulong and long route through the same helper; the fix is correct. ✓
• (ulong)Sum(static t => (long)t.Value.Count) — accumulates in 64-bit (long overload of Sum), then safely widened to ulong since counts are non-negative. ✓
• Dictionary<string, ...> keyed by address.ToString(withZeroX: true, withEip55Checksum: true) — the old Dictionary<AddressAsKey, ...> routed through AddressConverter.WriteAsPropertyName which outputs lowercase hex; the new approach pre-computes the EIP-55 key. ✓
• Dictionary<ulong, TransactionForRpc> keys — STJ uses the built-in decimal integer property-name serialization (no WriteAsPropertyName override on ULongConverter), so nonce 806 → "806" not "0x326". ✓
• MapTransactions returns new Dictionary<ulong, TransactionForRpc>(0) when address is missing → serializes as {}. ✓
• No LINQ in the new mapping helpers — manual foreach. ✓
• File-scoped namespaces on all new/converted files. ✓
• TransactionPoolContent.cs retains brace-style namespace — correct per the rule ("for existing files, follow their style"). ✓
• Test coverage: wire-format serialization tests for txpool_status hex counts, decimal nonce keys, null block fields, txpool_contentFrom filtering, and empty-address cases. ✓

[svlachakis]

@claude review again

[claude]

Claude finished @svlachakis's task in 2m 38s —— View job

---

PR Review: txpool: add txpool_contentFrom, fix txpool_status hex format

• Gather context and read relevant files
• Review changed files for correctness, security, and performance
• Check adherence to repo rules
• Post findings

---

Previous findings — status

#	Severity	Finding	Status
1	Medium	File naming: TxPoolContentFrom.cs → TransactionPoolContentFrom.cs	✅ Resolved
2	Low	Sum() accumulates in int, overflows before widening	✅ Resolved — (ulong)Sum(static t => (long)t.Value.Count)
3	Low	long vs ulong for pool counts	✅ Resolved — now ulong
4	Low	Missing XML doc comments on TxPoolContentFrom	✅ Resolved
5	Low	txpool_contentFrom ExampleResponse omitting blockTimestamp	✅ Resolved

---

New findings

Low

#	File	Issue
1	ITxPoolRpcModule.cs:16	txpool_content ExampleResponse omits blockTimestamp — The txpool_contentFrom example was fixed in this PR; the txpool_content example still has "blockNumber":null,"transactionIndex":null with blockTimestamp absent. The new test explicitly asserts blockTimestamp:null is always emitted. (Inline comment posted)
2	TxPoolRpcModule.cs:28	Missing null guard on address — address is untrusted RPC caller input; the robustness rules require ArgumentNullException.ThrowIfNull(address) before dereferencing it. A null address passes silently into AddressAsKey key = address and throws NullReferenceException. (Inline comment posted)

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What's correct

• ulong Pending/Queued + ULongConverter → hex wire format. ✓
• (ulong)Sum(static t => (long)t.Value.Count) — 64-bit accumulation, safe widening. ✓
• Dictionary<string, ...> keyed by address.ToString(withZeroX: true, withEip55Checksum: true) — correct EIP-55 keys. ✓
• Dictionary<ulong, TransactionForRpc> nonce keys — STJ decimal property-name serialization ("806" not "0x326"). ✓
• MapTransactions returns new Dictionary<ulong, TransactionForRpc>(0) on missing address → serializes as {}. ✓
• No LINQ in the new mapping helpers — manual foreach throughout. ✓
• File-scoped namespaces on all new/converted files. ✓
• TransactionPoolContent.cs retains brace-style namespace (existing file convention). ✓
• Test coverage: hex counts, decimal nonce keys, null block fields, filtering, empty-address cases. ✓

[svlachakis]

@claude review again

[claude]

Claude finished @svlachakis's task in 2m 33s —— View job

---

PR Review: txpool: add txpool_contentFrom, fix txpool_status hex format

• Gather context and read relevant files
• Review changed files for correctness, security, and performance
• Check adherence to repo rules
• Post findings

---

Previous findings — status

#	Severity	Finding	Status
1	Medium	File naming: TxPoolContentFrom.cs → TransactionPoolContentFrom.cs	✅ Resolved
2	Low	Sum() accumulates in int, overflows before widening to long	✅ Resolved — (ulong)Sum(static t => (long)t.Value.Count)
3	Low	long vs ulong for pool counts	✅ Resolved — now ulong
4	Low	Missing XML doc comments on new class	✅ Resolved — class summary and property <summary> docs added
5	Low	txpool_contentFrom ExampleResponse omitting blockTimestamp	✅ Resolved
6	Low	txpool_content ExampleResponse omitting blockTimestamp	✅ Resolved — "blockTimestamp":null is present in the example string
7	Low	Missing ArgumentNullException.ThrowIfNull(address) before dereferencing RPC input	✅ Resolved — TxPoolRpcModule.cs:31

---

New findings

None.

---

What's correct

• ulong Pending/Queued + ULongConverter → NumericConverterHelper.Write → hex wire format. ✓
• (ulong)Sum(static t => (long)t.Value.Count) — 64-bit accumulation, safe widening to ulong. ✓
• Dictionary<string, ...> keyed by address.ToString(withZeroX: true, withEip55Checksum: true) — correct EIP-55 keys on outer dict. ✓
• Dictionary<ulong, TransactionForRpc> nonce keys — STJ decimal property-name serialization ("806" not "0x326"). ✓
• MapTransactions returns new Dictionary<ulong, TransactionForRpc>(0) on missing address → serializes as {}. ✓
• ArgumentNullException.ThrowIfNull(address) guards the RPC input before any dereference. ✓
• No LINQ in new mapping helpers — manual foreach throughout. ✓
• File-scoped namespaces on all new/modified files (existing TransactionPoolContent.cs retains brace-style — correct). ✓
• Test coverage: hex counts, decimal nonce keys, null block fields, EIP-55 address keys, filtering, empty-address wire format. ✓

---

The PR is clean. All previously raised findings are resolved and no new issues were found.

[claude]

Claude finished @svlachakis's task in 2m 21s —— View job

---

PR Review: txpool: add txpool_contentFrom, fix txpool_status hex format, fix txpool_content

• Gather context and read relevant files
• Review changed files for correctness, security, and performance
• Check adherence to repo rules
• Post findings

---

Previous findings — status

#	Severity	Finding	Status
1	Medium	File naming: TxPoolContentFrom.cs → TransactionPoolContentFrom.cs	✅ Resolved
2	Low	Sum() accumulates in int, overflows before widening to long	✅ Resolved — (ulong)Sum(static t => (long)t.Value.Count)
3	Low	long vs ulong for pool counts	✅ Resolved — now ulong
4	Low	Missing XML doc comments on new class	✅ Resolved — class summary and property <summary> docs added
5	Low	txpool_contentFrom ExampleResponse omitting blockTimestamp	✅ Resolved
6	Low	txpool_content ExampleResponse omitting blockTimestamp	✅ Resolved
7	Low	Missing ArgumentNullException.ThrowIfNull(address) before dereferencing RPC input	✅ Resolved — TxPoolRpcModule.cs:31

---

New findings

None.

---

What's correct

• ulong Pending/Queued + ULongConverter → NumericConverterHelper.Write → hex wire format. ✓
• (ulong)Sum(static t => (long)t.Value.Count) — 64-bit accumulation, safe widening to ulong. ✓
• Dictionary<string, ...> keyed by address.ToString(withZeroX: true, withEip55Checksum: true) — correct EIP-55 keys on outer dict. ✓
• Dictionary<ulong, TransactionForRpc> nonce keys — STJ decimal property-name serialization ("806" not "0x326"). ✓
• MapTransactions returns new Dictionary<ulong, TransactionForRpc>(0) on missing address → serializes as {}. ✓
• ArgumentNullException.ThrowIfNull(address) guards the RPC input before any dereference. ✓
• No LINQ in new mapping helpers — manual foreach throughout. ✓
• File-scoped namespaces on all new/modified files (existing TransactionPoolContent.cs retains brace-style — correct per rule). ✓
• Test coverage: hex counts, decimal nonce keys, null block fields, EIP-55 address keys, filtering, empty-address wire format. ✓

---

The PR is clean. All previously raised findings are resolved and no new issues were found.

[Copilot]

Pull request overview

Note

Copilot was unable to run its full agentic suite in this review.

Implements missing txpool_contentFrom and aligns txpool RPC JSON serialization with the spec (hex-quantity counts and checksummed address keys), with added serialization-level tests.

Changes:

• Added txpool_contentFrom(Address address) RPC method + TxPoolContentFrom response model.
• Updated txpool_status response to serialize pending/queued as hex-encoded quantities.
• Updated txpool_content to emit EIP-55 checksummed address keys and refactored mapping logic.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/Nethermind/Nethermind.JsonRpc/Modules/TxPool/TxPoolRpcModule.cs	Adds txpool_contentFrom endpoint and modernizes module declaration.
src/Nethermind/Nethermind.JsonRpc/Modules/TxPool/TransactionPoolStatus.cs	Changes status counts to unsigned type for hex-quantity serialization.
src/Nethermind/Nethermind.JsonRpc/Modules/TxPool/TransactionPoolContentFrom.cs	Introduces response model that filters txpool content to a single sender.
src/Nethermind/Nethermind.JsonRpc/Modules/TxPool/TransactionPoolContent.cs	Emits checksummed address keys and refactors mapping to explicit loops.
src/Nethermind/Nethermind.JsonRpc/Modules/TxPool/ITxPoolRpcModule.cs	Adds new RPC method and updates txpool_status example response.
src/Nethermind/Nethermind.JsonRpc.Test/Modules/TxPoolRpcModuleTests.cs	Adds wire-format serialization tests covering status/content/contentFrom behaviors.

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[batrr]

Would be nice to address the allocation/perf comments from #11048; not critical though

[svlachakis]

@batrr it becomes very messy because we would need two GetInfo() & GetInfo(Address)..that's why I didn't.

• GetInfo() - full pool scan, used by txpool_content, txpool_status, and txpool_inspect (all need the whole pool)
• GetInfo(Address) - single-address scan, used only by txpool_contentFrom

There's no way to collapse them without regressing the other three methods. The only way to eliminate GetInfo() entirely would be to rewrite txpool_status to count directly (without building the full TxPoolInfo) and similarly for the others but that's a broader refactor that I can do as a separate PR.